As to this debate, the best piece of advice I can give you is to fast-forward to 15 minutes or so when the moderator finally starts talking, after all the reading and praying and chanting. At 18 minutes it, the moderator lays down a "No ridicule of Allah" rule, thus demonstrating a rather pinched and distinctly Islamic view of what constitutes open debate in a free society, not to mention a certain degree of monotheistic hypocrisy given the countless verses of Quranic abuse heaped upon the gods of the polytheists. Come to think of it, just fast-forward to around 22:30 when they finally get down to the debate itself. There, now never let it be said that I've never done you any favors.
Rajabali leads off, oddly enough, with several apologetical counterarguments against common atheist arguments, most particularly the argument from evil. His answer to the problem of evil is that life is a test for the sake of the hereafter, hence the obvious need for genocide and rape. He also argues that without an afterlife, injustice turns out to be truly unjust, even in the long run. Corey basically argues from apparent fine-tuning, paraphrasing the arguments from his book.
Barker leads off with the "graveyard of gods" and "one less god than you" argument, which I've never considered terribly impressive, at least not as formulated. It does give him a chance to make clear that the no ridicule rule applies only to Jehovah/Allah. He then points out that "gods or the gaps" thinking stops the advance of scientific discovery. He also runs a couple of incompatible properties arguments, which I think are generally underutilized in such forums. He goes on to point out that the fact that monotheists kill each other over alleged heresies makes it difficult for unbelievers to take any particular kind of monotheism seriously. He then runs a particularly devastating version of the argument from evil, calling God a bystander on 9/11 and an accomplice to mass murder.
Carrier provides, in his usual fashion, a fairly complete and compelling argument that blind mechanistic forces are the only things running the universe, and indeed the multiverse.
The rebuttals were substantively fairly predictable, with each side crying that the other side may some fundamental mistake or another. Entertainly, though, Rajabali sounds a bit like he is frothing at the mouth and about to kick off a riot. "Are you schismatic?!?" he shouts, in the tones of a witchfinder or inquisitor. I've got to say, this guy managed to live down to my expectations for Muslim dialogue, confirming several stereotypes which I'd prefer to have had disconfirmed.
Overall, the theists did a good job of presenting and defending the fine-tuning argument, while the nontheists did a fairly good job all around. For a more detailed breakdown of this debate, you might want to read Carrier's take.
Overall rating: 4
Believer rating: 3.25
Unbeleiver rating: 4.75